Field of the Invention
The invention relates to a light source module and a display apparatus, and more specifically to a light source module having two light guide plates and a display apparatus.
Description of Related Art
Liquid crystal displays (LCD) have been broadly applied in various aspects of our daily life, such as being applied in informational household appliances including notebooks, liquid crystal monitors, portable consumer audio-video products, mobile phones, and liquid crystal TVs, etc. Since the display panel in a liquid crystal display does not emit light, the light source module that provides light is a key component of the liquid crystal display.
In relevant research on displays in recent years, the anti-spy function of displays becomes more and more important. Since users hope that, when using relevant products, the individual privacy may also be protected, more and more people add an anti-spy function to their screens, and the products suitable for adding the anti-spy capability expand further from notebook computers and liquid crystal monitors to portable consumer audio-video products, such as mobile phones and tablets, etc. Currently, the main stream of the anti-spy design is to add an anti-spy film to shield a large angular beam, so as to prevent others from viewing. However, such anti-spy film makes the brightness in the front perspective lower and reduces the display sharpness. Also, the user must carry the anti-spy film all the time, making it inconvenient to use. Alternatively, some technologies utilize the spirality of twist nematic (TN) liquid crystal in different blocks of the screen, such that the viewer may perceive different brightnesses at different angles, thereby accomplishing the effect of anti-spy. However, controlling the liquid crystal molecules to have different inclination angles in different display areas make the manufacturing process more difficult. Another alternative is to utilize the optical properties of the vertically aligned (VA) liquid crystal to produce a designed anti-spy pattern on the mobile phone to interfere others' viewing. However, such technology makes the brightness of the mobile phone lower, and the designed anti-spy pattern is unable to completely shield the contents being displayed. Thus, the anti-spy effect of the display is not desirable.
Moreover, users also desire to optionally select whether to use anti-spy function. Therefore, their own privacy is protected after the anti-spy function is used, and others may view the contents of the display after the anti-spy function is not used. Consequently, how to make the display have a good anti-spy effect and to optionally select whether to use the anti-spy function is indeed one of the topics that researchers in this field commit their self to.
The information disclosed in this “BACKGROUND OF THE INVENTION” section is only for enhancement of understanding of the background of the described technology, and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in this “BACKGROUND OF THE INVENTION” section does not mean that one or more problems to be resolved by one or more embodiments of the invention was acknowledged by a person of ordinary skill in the art.